From an Aliphatic Substrate

Such syntheses are more suited to the preparation of hydro rather than aromatic 1,8-naphthyridines and may require auxiliary synthons. A few typical examples follow. 

4-Trichloro-4,6-dicyanohexanoyl chloride (1) gave 3,7-dichloro-l,8-naphthyridin-2(17/)-one (2) (HC1, Bu20, 140°C 78%).715 

The Naphthyridines The Chemistry of Heterocyclic Compounds, Volume 63, by D.J. Brown Copyright 2008 John Wiley Sons, Inc. 

A -(2-Benzoylethyl)-AvV-dimethylammonium chloride (2 mol) and cyanoaceta-midinium chloride (made in situ) gave 2,7-diphenyl-l,4,4a,5-tetrahydro-l,8-naphthyridine-4a-carbonitrile (6) (HC1 52%).1402 

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